1 research outputs found
Carbon Dioxide Adsorption onto Polyethylenimine-Functionalized Porous Chitosan Beads
Polyethylenimine-functionalized
porous chitosan (PEI–CS)
beads were prepared and their CO<sub>2</sub> adsorption performance
was evaluated. The CO<sub>2</sub> adsorption capacity of PEI–CS
was dependent upon both the amine content and surface area of the
functionalized beads. PEI–CS showed a CO<sub>2</sub> adsorption
capacity of 2.3 mmol/g at 313 K and 15 kPa of CO<sub>2</sub> in the
absence of water vapor that considerably increased to 3.6 mmol/g in
the presence of water vapor. To rationalize this phenomenon, the CO<sub>2</sub> adsorption mechanisms in the absence and presence of water
vapor were investigated by diffuse reflectance infrared Fourier transform
spectroscopy. The results indicated that the mechanism of CO<sub>2</sub> adsorption onto PEI–CS, in both the absence and presence
of water vapor, involved the formation of carbamate. Therefore, the
higher CO<sub>2</sub> adsorption capacity in the presence of water
vapor was attributed to the increased accessibility to amino groups
of PEI–CS, owing to swelling of the polyethylenimine chain
and/or chitosan framework upon adsorption of water. The herein reported
chitosan-based material displays high CO<sub>2</sub> adsorption capacity
as well as excellent regenerability and, thereby, shows potential
as an adsorbent for CO<sub>2</sub> capture